Geant4 General Particle Source

Whilst the default particle generator within Geant4 (G4ParticleGun) may be suitable for simple studies in accelerator physics, the potential complexity of the primary particle distributions within the space environment necessitates a more sophisticated sampling algorithm. The General Particle Source (GPS, G4 class name: G4GeneralParticleSource) allows the user to utilise standard energy, angular and spatial distributions:

1. Spectrum: linear, exponential, power-law, Gaussian, blackbody, or piece-wise fits to data.
2. Angular distribution: unidirectional, isotropic, cosine-law, beam or arbitrary (user defined).
3. Spatial sampling: on simple 2D or 3D surfaces such as discs, spheres, and boxes.
4. Multiple sources: multiple independent sources can be used in the same run.

The GPS includes methods to bias the sampling distribution. This feature permits, for example, more particles to be sampled closer to the area of the spacecraft where greater sensitivity to radiation effects is expected.

To use the G4GeneralParticleSource, simply replace "G4ParticleGun" with "G4GeneralParticleSource" in the PrimaryGeneratorAction class files of your application.

Further information on the General Source Particle Module can be found in the documents listed on the left.

News:

29-Oct-2004: New features added (event-V06-01-02):

  i) Focused angular distribution
  ii) Multiple primary vertices
  iii) Separate biased theta and phi generators for positional and angular distributions.

User manual has been updated and a G4 extended example has been created to demonstrate the usage of G4GeneralParticleSource. The example is in examples/extended/eventgenerator/exgps (tag: exgps-V06-02-00).

26-Apr-2004: Tag event-V06-01-02. Restored a few methods to G4GeneralParticleSource to improve
backward compatibility. So there is no need to chnage old applications for most applications.

05-Apr-2004: Lattest version now in the Geant4 repository (tag: event-V06-01-01).
                           User manual and examples all have been updated.

02-Apr-2004: Lattest version now in the Geant4 repository (tag: event-V06-01-00).

10-02-2004: Major updates to GPS completed. Please see the release note.

20-10-2003: Made the lattest tag available to the public users. See Source Code on the right.

26-09-2003: We plan to carry out a design interation of the G4GeneraparticleSource class. Please send your comments, suggestions, and new requirements to us.

01-03-2003: Web version of the Software User Manual (SUM) is available on-line.

01-10-2001: Added Beam option for generating accerlator beams (2d profile)

19-07-2001: Most commands under G4ParticleGun class are now available under GPS